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1.
This study was designed to determine metabolic and physical performance responses to ingestion of pre-exercise meals with different macronutrient and fiber profiles. Twelve physically active subjects (6 males and 6 females) were used to investigate the metabolic and physical performance consequences of consuming pre-exercise meals consisting of oat, corn, or wheat cereals. A fasting trial served as the control, and all subjects received each treatment in a Latin-square design. Blood samples were drawn before and 85 min after meal ingestion, during 90 min of cycling exercise (60% VO2peak), after a 6.4 km performance ride, and during 60 min of recovery. Expired air samples were collected to determine nutrient utilization. Resting carbohydrate oxidation rates and plasma insulin concentrations after oat ingestion were less than after wheat, and corn and wheat ingestion, respectively (P < 0.05). During exercise, the change in plasma glucose from pre-exercise was greater after consuming wheat and corn compared with oat (P < 0.05), and it was inversely related to pre-exercise plasma insulin concentration (r = -0.55, P = 0.0001). Plasma free fatty acid concentrations were inversely related to plasma lactate concentrations (r = -0.58, P = 0.0001). Free fatty acid concentrations and fat oxidation were greater in fasting trials than all others, but performance ride times did not differ among treatments. Plasma branched-chain amino acid concentrations resembled their respective meal profiles throughout exercise, the performance ride, and recovery. These results indicate that pre-exercise meal composition can influence glucose homeostasis during early exercise and plasma branched-chain amino acid concentrations over a substantial range of metabolic demands.  相似文献   
2.
Ultrasonic methods are being developed for sensing and control of high temperature material processes such as welding and solidification. One of the problems in these methods is the distortion of the sound field caused by the change in material properties due to temperature gradients. This paper describes a ray-tracing method for calculating the effects of temperature on ultrasonic propagation in such systems. In the ray-tracing method, the material is conceptually divided into a number of plane layers. The refraction at each layer boundary is calculated from Snell's law using the sound speeds determined from the temperatures of the adjacent layers. The time required for an ultrasonic pulse to traverse each layer is also calculated, allowing the determination of the total time along a particular path. The method is applied to calculating the time of arrival of echoes from various interfaces around a molten weld pool.  相似文献   
3.
This article replies to comments by J. C. Gonsiorek (see record 84-33291), P. Orr (see record 84-33300), and L. S. Brown (see record 84-33284 ) on M.J. Layman and J.R. McNamara's (see record 84-33293) work on remediation and ethics violations. The authors acknowledge various distinctions they have introduced but continue to argue that sexual violations are outstandingly egregious. They agree that making amends is important but wonder about the practicalities of working this into rehabilitation. Lack of empirical knowledge about what is prescribed for remediation is reemphasized. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
The field of psychology has only recently begun to recognize the extent and impact of professional impairment of its members, whereas several other professions have established formal identification and treatment plans for impaired colleagues. Impairment in psychologists may be caused by various factors, but it has the same result: diminished levels of care and, frequently, ethics violations. Sexual contact with clients is considered in particular. Several alternate avenues for remediation exist, including mandatory psychotherapy for ethics offenders. Although the majority of psychologists value personal therapy for training purposes, it is the authors' opinion that mandated therapy is not an appropriate form of rehabilitation for such violations of the ethics code. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Accurate determination of MOSFET effective channel width Weff is important for process control and device design. Existing methods to determine Weff are sensitive to measurement noise, and to nonlinearities in the data. In this paper we present a new method to determine Weff that overcomes these problems. The method uses nonlinear optimization, and is based on a drain current model that accounts for the variations of Weff, of series resistance, and of threshold voltage, with masked channel width and gate bias. We also show that our new method is more accurate and less sensitive to measurement procedure than other methods.  相似文献   
6.
Highly branched poly(arylene ether sulfone)s with systematically varied degrees of branching and sulfonation were synthesized through oligomeric A2 + B3 methods for application as ionic polymer transducer (IPT) membranes. IPTs are a class of electroactive polymer devices that leverage ionomeric membranes to perform electromechanical transduction as actuators and/or sensors. Synthesis of controlled molecular weight A2 oligomeric polysulfones targeted the global degree of branching (DBglobal) to approximately 1–3% in the absence of gelation. Size exclusion chromatography confirmed molecular weights greater than 20 000 g mol?1 were achieved for linear and branched polysulfones. Increased degree of sulfonation of the A2 oligomers reduced the development of molecular weight in the oligomeric A2 + B3 branching reaction; the formation of tough, flexible, ion‐conducting membranes is required for emerging transducer applications. Variation in the DBglobal attained did not affect the thermal transitions or elastic modulus as significantly as changes in the degree of sulfonation. However, an ionic dissociation temperature was detected below the glass transition temperature of the polysulfone matrix and was relatively independent of the degree of sulfonation. Successful synthesis and characterization of these well‐defined branched polysulfone ionomers provide a basis for future investigation of polymer topology effects on IPT performance. Copyright © 2009 Society of Chemical Industry  相似文献   
7.
We report the first case of dicavitary twin pregnancy, following clomiphene citrate therapy, in a patient with uterus bicornis bicollis and anovulation. A review of the literature is presented, and obstetric outcomes and management of these rare pregnancies are discussed.  相似文献   
8.
Design requirements for the advanced light water reactor (ALWR) have been developed so as to provide high assurance of containment integrity even in the event of a severe accident. The containment integrity requirements are in the form of two design criteria, and associated methodology, which address containment severe accident performance and offsite dose and are specified in the ALWR utility requirements document (URD), a set of detailed design requirements for next generation plants in the US.The containment performance criterion, which is the main focus of this paper, specifies that plant design characteristics and features shall be provided to preclude core damage sequences which could bypass containment and to withstand core damage sequence loads. This containment performance capability, along with the associated dose mitigation capability, provides a technical basis for emergency planning change since there would not be the same need for rapid offsite emergency response that is called for under the existing US emergency planning basis.  相似文献   
9.
A compact VLSI MOSFET model that includes an integrated thermal noise model and a methodology for the analysis of the effects of thermal noise on the performance and error rates of digital integrated circuits is presented. The usefulness of the model and methodology is demonstrated by comparing simulation results for signal-to-noise ratio to analytic results for the balanced bit-line architecture of the single-device DRAM and the associated cross-coupled pair sense amplifier. The design options and tradeoffs related to thermal noise are introduced for both the balanced bit lines and the sense amplifier are considered. The error rate as a function of signal-to-noise ratio is determined, and possible limits to DRAM construction due to inherent thermal noise are highlighted  相似文献   
10.
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